稀土功能配合物在荧光传感方面的发展及应用

Development and Application of Rare Earth Functional Complexes in Fluorescence Sensing

摘要: 稀土功能配合物以稀土离子为中心，通过配位键与配体结合，凭借4f电子独特屏蔽效应、宇称禁阻跃迁、强自旋–轨道耦合，以及高配位数、多变配位几何和特有顺磁性，展现出优异的光学、磁学性能，在荧光传感领域具备核心应用价值。其荧光传感以配体–稀土离子的天线效应为基础，核心机制分为荧光猝灭或增强、比率检测、时间分辨发光及荧光颜色可调四类，可通过荧光信号变化实现目标物精准识别，兼具快速响应、低检测限、高选择性等优势。总结了配体设计、纳米限域、表面功能化及异金属掺杂等性能优化策略，可有效提升配合物的能量转移效率、稳定性、分散性与靶向识别能力。目前该类材料已广泛应用于金属离子、阴离子、有机污染物等环境污染物检测，以及细胞生物成像等生物医学领域，能克服传统检测方法背景干扰大、灵敏度低等局限，在痕量分析、活体可视化检测中表现突出。近年来，稀土功能配合物的结构设计与传感应用随多学科交叉快速发展，但仍存在水稳定性、生物相容性不足等问题。稀土功能配合物荧光传感性能优异，但受多重瓶颈制约，未来需多方向协同优化，推动其在多领域落地应用。

Abstract: Rare-earth functional complexes, with rare-earth ions as central metal nodes coordinated to ligands via coordination bonds, exhibit remarkable optical and magnetic properties owing to the unique shielding effect of 4f electrons, parity-forbidden transitions, strong spin-orbit coupling, high coordination numbers, flexible coordination geometries, and intrinsic paramagnetism. These features endow them with significant potential in the field of fluorescent sensing. Their sensing behavior is primarily based on the antenna effect between ligands and rare-earth ions. The fundamental mechanisms can be categorized into fluorescence quenching or enhancement, ratiometric sensing, time-resolved luminescence, and tunable emission color. Through variations in fluorescence signals, target analytes can be accurately identified, offering advantages such as rapid response, low detection limits, and high selectivity. Strategies for performance optimization—including ligand design, nanoscale confinement, surface functionalization, and heterometal doping—have been summarized, which effectively enhance energy transfer efficiency, stability, dispersibility, and target recognition capability of the complexes. At present, these materials have been widely applied in the detection of environmental pollutants such as metal ions, anions, and organic contaminants, as well as in biomedical fields including cellular imaging. They can overcome the limitations of conventional detection methods, such as strong background interference and low sensitivity, and demonstrate outstanding performance in trace analysis and in situ bioimaging. In recent years, the structural design and sensing applications of rare-earth functional complexes have rapidly advanced with interdisciplinary development. However, challenges such as insufficient water stability and limited biocompatibility still remain. Despite their excellent fluorescence sensing performance, these materials are constrained by multiple bottlenecks, and future efforts should focus on synergistic optimization from multiple perspectives to promote their practical applications across diverse fields.